13th Jan 2005, 09:31

I have recently purchased a Daihatsu "S85 Hi-jet Glass van" with 16,250 miles on the clock. It tends to over eat very quickly. I have removed the thermostat, which improved matters on open road driving, but within 20 or so minutes of town use it will overheat and lose up to a litre of coolant. Can't get much joy out of local agents. I have one theory of cure and that is to somehow induce the fan to motivate at a lower temperature, but as the vehicle came with no manuals or notes, I don't know how to execute the task. A kindly word or manufacturer's contact name would be appreciated.

28th Aug 2007, 18:48

Hi

I have had five Hi-jet vans over the years, and the best one to have is the 1,000cc 3cyl. I agree that the 1300 is very thirsty, and I noticed that compared to the 1000cc you had to slip the clutch to get it on its way. The gearbox and engine I think was lifted straight out of a car, and didn't suit the van at all. The 1000cc was a proper van gearbox.

The 1000 cc has great fuel economy, and has more Daihatsu (Made in Japan) parts, so was a more reliable van.

Forget the Extol; it's lost the plot with its false floor ie to make a totally flat deck over the wheel arches (who asked for that) so creating a smaller load carrying capacity.

Can anybody comment on the Piaggio versions as I need to purchase a new van sometime in the future. Are they has durable, or has the OK quality gone down?

30th Apr 2010, 07:55

I own and run a 1.3 efi Hijet MPV. It is fantastic, the fuel economy is fantastic at about 45-50mpg.

It's pretty quick for such an odd machine, top speed I'm not sure of as mine goes off the clock (90mph) easily on the motorway. Fits all sorts in the back, great if you're doing up a house or moving home etc.

There are many great aspects of such a small nippy machine that I could go on about. Cheap insurance, cheap tax, and tyres and brakes are really cheap. LPG ones are easily found, making motoring very very cheap.

The Hijets do have their negative features! Good side winds make for interesting driving, you have to concentrate on the motorway because the pressure waves in front of trucks push you about. They rot pretty bad, round all the inner arches and a few other places. They burn oil if they have been ragged hard, and overheat if the coolant system isn't 100%. The ride over bumpy stuff and speed humps is quite abusive!

All in all, I love my Hijet, I get all the use of running a good sized van, while it's got the performance and costs of running a little hatch back car. Plus people smile and wave!

22nd Oct 2011, 21:55

My 1300 cc EFI Hi-Jet overheated without warning. I had been doing the normal checks, A.K.A. the "Owners Manual", including water level in the overflow reservoir bottle; which appeared OK.

However removing the engine filler cap (not the lower one on the radiator), showed a problem: low water level in the engine.

Immediate "get me home" solution, was to refill with a surprisingly small amount of water - about 3/4 of a litre.

The next clue showed the next day, with a cold engine; the radiator-to-engine hoses were partially collapsed under vacuum.

Assuming the vacuum should draw water (and not air) from the reservoir back into the engine as it cools, then the filler cap mechanism was suspect. A replacement cost less than £6 from a local auto-spares shop; it is a generic "fits lots of Japanese engines" size apparently.

Something so simple as replacing filler cap fixed the problem: it has not overheated since, hoses don't collapse, and the reservoir level goes up and down a little between hot and cold.

Of course if that had not worked, there could be other things I've had to check on my previous cars:

Check for water circulation by feeling hoses heating up when the thermostat lifts; they remain coldish until it does lift, then rapidly heat up with full circulation.

No circulation could be caused by:

* Low water level (or air-locks)? - my problem; refill system from highest filler cap - the one one on the engine, and recheck it's still full after warming up, (i.e. no trapped air).

* Thermostat not opening? Try putting it into a pan of water and bringing it to the boil.

* Problems with water pump? Check also for loose fan-belt?

* Sludge or blockage in radiator? Try reverse flushing out with a garden hose pipe.

Also notice that the temperature indicator should drop fairly quickly when the electric fan cuts in; these fans blow a strong hot wind, which can be felt at side or rear of car. This shows that heat is being moved rapidly from the engine to the radiator, and thus we have good water circulation.

Another clue to my low-water fault, which I missed the importance of at the time, was it was overheating and the electric fan was not switching on. This was on a cold night, on a short uninterrupted journey; i.e. it was not standing in traffic but moving, under conditions when the fan should not be required.

Normally in slow traffic, you'd expect the fan to run when the engine is hot, but it should not need to if cold air is freely moving through radiator, i.e. we're moving.

However no matter what, if we're overheating, the fan should be switched on by its thermostatic switch. In the past I've had one fail on a previous car; a Ford (see footnote), so I was thinking the fault was the same. In retrospect this was not following all the clues, because if we're low on water, the electric fan switch becomes uncovered, hence does not sense any rise in temperature, so the fan does not run. So beware of this second reason why the fan doesn't run.

As an aside, I cannot understand why engine designers place fan sensors (and water pumps) high up in the water loop, where only a very small drop in water level causes them to stop working. Maybe it is one of those things copied stupidly from previous generations 'because it always works that way'.

I draw some conclusions from my overheating fault:

1. Don't just rely on checking the level of the reservoir; also look at hoses for other faults; which I suppose should be done anyway; looking for leaks et cetera.

2. It takes very little drop in water level inside the engine for it to overheat, maybe 'cos engine is so tipped over on its side, the water pump may then find itself whirling in air and circulation stops.

3. Is the fan running? Work out if it should be running, are we in traffic or free moving? If free moving, then the primary fault is not the fan because it should not be necessary. However, we can still use it as additional clue.

4. Water circulation is everything to effective cooling. What can be stopping or reducing it? Think of how much heat it can quickly shift when it wants to, or mundanely to warm up your toes on a cold day.

5. Are hoses hot or cold? If cold, then we have air blockage, and/or no circulation. However my hoses did eventually become hot when the engine overheated, because of the steam produced. So think about WHEN you touch them: is the engine cold? Should the thermostat have opened? Is it blowing-off steam, misleading me?

Footnotes:

My previous car, a Ford, gave me lots of trouble because I was not 'up-to-speed' with all of its symptoms:

At some time, its fan stopped working when in slow traffic conditions; changing it soon restored function. So I thought all was well.

However the front window tended to be heavily misted up inside in the mornings; I misread that as merely because that was the end facing away from the rising morning Sun.

What I failed to notice, was that the heater matrix was slowly leaking onto the carpet, which was making the humidity at the front of the car mist up the window. But that water was coming from the engine coolant, and eventually it dropped so low as to overheat when on a fast road. That caused the header gasket to blow and the casting to fracture. My first ever emergency tow home!

So always watch and listen to what the car is trying to say, even if it is just some regular heavy morning condensation.

N.B. I use my local independent spares shop regularly, because he is fair on price, but also checks the sizes of spares for all makes of cars on a suppliers' computer database; so the Internet does have some real 'proper' uses! For example, on another visit, my 2002 EFI Hi-Jet has a standard 45-AH battery, but these come with either small or large terminals. Another visit, the rear brake shoes may be either 180mm or 200mm (8 or 10 inch) diameter. So always double check sizes and fit of spares; preferably before driving away from the shop!